A pathological and microbiological evaluation of omphalophlebitis in very young calves slaughtered in New Zealand

Omphalophlebitis, generally referred to as navel ill, is a common post-mortem meat inspection finding in very young calves slaughtered in New Zealand, and a gross pathological, histopathological and bacteriological evaluation of 147 carcasses condemned for this condition at routine post-mortem meat inspection was undertaken. Localised lesions restricted to the umbilicus alone were present in 29.9% of cases. The majority of cases included gross pathological change in the umbilical vessels and other tissue sites beyond the umbilicus. Most hepatic nodes were grossly normal but histological examination revealed that 61.5% of nodes from other than localised cases of navel ill were hyperplastic. However, there was little difference in the prevalence of hyperplastic hepatic nodes from cases of localised navel ill (21.4%) compared with normal calves (15.9%). Despite the wide range of bacteria isolated from umbilical lesions, Salmonella typhimurium recovered from the navel, liver and hepatic nodes of a single extended case of navel ill was the only isolation of known public health importance. Given the separation of cases of navel ill into different gross pathological, histopathological and microbiological categories, current meat inspection judgments whereby all calves with navel ill are condemned should be revised. In particular, routine condemnation of the carcass and viscera in all cases of localised navel ill (lesions restricted to the umbilicus alone) should be reassessed.     

Particles floating on a moving fluid: a dynamically comprehensible physical fractal

Measurements of the local dynamics on the surface of a fluid undergoing complicated motion allow prediction of the measured fractal dimension of an aggregate of passive, floating tracers. This realization of a strange attractor in physical space is a rare instance where there is a firm quantitative connection between the dimension of an experimentally observed fractal spatial pattern and the process producing it.     

Segregation and linkage analysis of DNA markers in microspore derived and F2 populations of oilseed rape (Brassica napus L.)

Summary The segregation of RFLP and RAPD markers was compared in two oilseed rape (Brassica napus L.) breeding populations from the cross Topas x R4, the latter being a low linolenic mutation line. A total progeny of 68 F₂ and 40 microspore derived plants were studied with 25 markers. The results indicated a significant excess of Topas alleles at five RAPD loci in the microspore derived population. This suggests that genomic regions which probably affect microspore culture ability do not have identical distribution in the two population types.     

Measurement of endogenous amino acid losses in poultry

1. Ileal endogenous amino acid losses were determined in broiler chickens and in cannulated cross‐bred layer strain cockerels using either a nitrogen‐free diet, regression analysis or a 48 h fast.

2. Endogenous amino acid flows to the ileum in fasted cockerels were significantly lower than those obtained both by feeding the nitrogen‐free diet, and from regression analysis in either broilers or cockerels. Regression analysis gave the highest flows.

3. The apparent digestibility coefficients of amino acids in a diet containing 200 g/kg crude protein were lower in broilers (0.84) than in cockerels (0.88). When corrected, by regression analysis, for the contribution of endogenous amino acids, the true digestibility coefficients became 0.90 and 0.92 respectively.